Let us understand the basic process of chromatography…. Chromatography is a technique for separating mixtures into their pure components in order to analyze, identify, purify, and/or quantify the mixture or components. Separation and Quantification Separate Quantify Mixture Components

Applications for Paper Chromatography Preparatory Analytical Chromatography is used for: Ink analysis Forensic analysis Pharmaceuticals Dyes and pigments Food colouring Plant constituents ……………..

Separation of Ink components Activity: Ink is placed on filter paper (water bound in Cellulose stationary phase) Solvent(mobile phase) is soaked up & passes through the filter paper Mobile phase carries the ink components and causes separation based on the difference in migration rates.

Paper Chromatography Experiment Which pen wrote the note?

Migration rates: Rf value The distance travelled relative to the solvent is called the Rf value Formula: Rf = distance travelled by compound distance travelled by solvent. Thus, the higher the Rf value, the further the compound will travel up the paper. The Rf value is used to compare values similar values and conclude that they are indeed the same compound.

Factors which will affect Rf value Type of paper Solvent composition Temperature Chamber saturation Factors which will NOT affect Rf value Solvent volume Size of paper Sample size

Types of Paper chromatography Development methods based on direction of flow of mobile phase Descending Paper Chromatography Circular / Radial Paper Chromatography Multi-dimentional Ascending Descending Circular Multi-dimentional

Methods of detection UV chamber: densitometer Spraying of chemical indicators: Ninhydrin Iodine vapours

Pharmaceutical applications of paper chromatography: separation /identification Amino acids and organic acids Alkaloids Polysaccharides Proteins and peptides Natural and artificial pigments Inorganic cations Plant extracts Reaction monitoring Isolation & Purification